Answer:
please see answers below
Explanation:
13a)
120 books at £4 each = £480
he sells 60 books at £5 each = £300
he sells 40% of 120 books (48 books) at £7 each = £336
he has sold 60 + 48 books = 108 books.
he has 120 - 108 = 12 remaining.
he sells these 12 at £8 each = £96.
his sales are 300 + 336 + 96 = £732.
formula for percentage profit = (profit/cost price) X 100
= [(732 - 480) / 480] X 100
= (252/480) X 100
= 52.5%
13b) £15 is 120% of the price
15/120 = 0.125 is 1% of the price
so 100 X 0.125 = £12.50 is 100% of the price (ie the value in May 2018)